using System;

using System.Globalization;

public class Program

{

    public static void Main()

    {

        var formatString = string.Format(CultureInfo.InvariantCulture, "D{0}", DateTime.MaxValue.Ticks.ToString(CultureInfo.InvariantCulture).Length);

        var rowkey = DateTime.Parse("2018-05-17T01:59:35.678Z").Ticks.ToString(formatString, CultureInfo.InvariantCulture);

        Console.WriteLine($"a row key: \n\t{rowkey}");

        Console.WriteLine($"UtcNow.AddMinutes(-5): \n\t{DateTime.UtcNow.AddMinutes(-5).Ticks.ToString(formatString, CultureInfo.InvariantCulture)}");

        Console.WriteLine($"specific dates key: \n\t{DateTime.Parse("2018-05-17T21:02:34.1903256Z").AddMinutes(-5).Ticks.ToString(formatString, CultureInfo.InvariantCulture)}");

        Console.WriteLine($"a keys date: \n\t{DateTime.SpecifyKind(new DateTime(Convert.ToInt64("0636622212954153029")), DateTimeKind.Utc):O}");

        Console.WriteLine($"a keys date: \n\t{DateTime.SpecifyKind(new DateTime(Convert.ToInt64("0636622154327360547")), DateTimeKind.Utc):O}");

​

        var dateFrom = DateTime.Parse("5/9/2018 8:03");

        var dateTo   = DateTime.Parse("5/8/2018 17:39");

        Console.WriteLine((dateFrom-dateTo).TotalMinutes);

    }

}